Core B "remodeling histology" will support all four individual projects by providing quantitative analysis of airway remodeling end-points in mice subjected to repetitive allergen challenge. The core will quantitate structural remodeling changes in the airway focusing particular on peribronchial fibrosis and smooth muscle changes. The core will perform staining (trichrome), and immunostaining (a-smooth muscle actin, collagen III and V) of coded lung sections and utilize image analysis to quantify results. Additional assays available in the core include total lung collagen measurements, and assessment of epithelial mucus expression.